Appendix 14.1 Navigational Risk Assessment

105 Pages·2014·12.19 MB·English

Tidal Lagoon Swansea Bay plc

Appendix 14.1
Navigational Risk Assessment

Tidal Lagoon Swansea Bay – Environmental Statement Volume 3
Appendix 14.1
Tidal Lagoon Swansea Bay plc

Swansea Bay Tidal Lagoon

Navigational Risk Assessment

Prepared by: Anatec Limited

Presented to: Tidal Lagoon (Swansea Bay) plc
Date: January 2014
Revision No.: 01
Ref: A3025-TLP-NRA-1
Tidal Lagoon Swansea Bay plc

This study has been carried out by Anatec Ltd on behalf of Tidal Lagoon (Swansea Bay) plc. The
assessment represents Anatec’s best judgment based on the information available at the time of
preparation and the content of this document should not be edited without approval from Anatec.
Any use which a third party makes of this report is the responsibility of such third party. Anatec
accepts no responsibility for damages suffered as a result of decisions made or actions taken in
reliance on information contained in this report.
Tidal Lagoon Swansea Bay plc

TABLE OF CONTENTS
1.0 INTRODUCTION .............................................................................................................. 1
1.1 BACKGROUND ................................................................................................................. 1
1.2 SITE OVERVIEW AND THE PROJECT ....................................................................................... 1
1.3 CONSTRUCTION WORKS AND MARINE TRAFFIC ....................................................................... 2
TABLE 1.1 SUMMARY OF CONSTRUCTION PLANT/VESSELS ...................................................... 4
2.0 GUIDANCE ...................................................................................................................... 5
2.1 PRIMARY GUIDANCE ......................................................................................................... 5
2.2 SECONDARY GUIDANCE ..................................................................................................... 5
3.0 DATA SOURCES ............................................................................................................... 6
3.1 AIS DATA AND COMMERCIAL VESSEL MOVEMENTS ................................................................. 6
3.2 RECREATIONAL ACTIVITY ................................................................................................... 7
3.3 FISHING ACTIVITY ............................................................................................................. 7
3.4 MARINE AGGREGATE AREAS ............................................................................................... 7
3.5 OTHER RENEWABLE ENERGY DEVELOPMENTS ......................................................................... 7
3.6 OIL AND GAS INSTALLATIONS .............................................................................................. 8
3.7 NAVIGATIONAL FEATURES.................................................................................................. 8
4.0 BASELINE ENVIRONMENT .............................................................................................. 9
4.1 NAVIGATIONAL FEATURES.................................................................................................. 9
4.2 PORTS IN CLOSE PROXIMITY TO THE PROJECT ......................................................................... 9
4.3 ANCHORING ................................................................................................................. 10
4.4 AIDS TO NAVIGATION (ATON) ......................................................................................... 12
4.5 SAILING DIRECTIONS ...................................................................................................... 13
4.6 OTHER RECEPTORS ......................................................................................................... 13
5.0 METOCEAN DATA ......................................................................................................... 17
5.1 GENERAL SITUATION ...................................................................................................... 17
5.2 TIDES .......................................................................................................................... 17
5.3 COASTAL PROCESSES ...................................................................................................... 19
6.0 EMERGENCY RESPONSE OVERVIEW AND ASSESSMENT .............................................. 20
6.2 SAR HELICOPTERS ......................................................................................................... 20
6.3 EMERGENCY TOWING VESSELS .......................................................................................... 22
6.4 RNLI LIFEBOATS ............................................................................................................ 22
6.5 SAR LIAISON ................................................................................................................ 23
7.0 MARITIME INCIDENTS .................................................................................................. 24
7.1 INTRODUCTION ............................................................................................................. 24
7.2 MARINE ACCIDENT INVESTIGATION BRANCH (MAIB) ........................................................... 24
7.3 RNLI .......................................................................................................................... 25
8.0 MARINE TRAFFIC ANALYSIS .......................................................................................... 27
8.1 INTRODUCTION ............................................................................................................. 27
8.2 VESSEL LENGTH ............................................................................................................. 34
Tidal Lagoon Swansea Bay plc

8.3 VESSEL DRAUGHT .......................................................................................................... 35
8.4 VESSEL COURSES............................................................................................................ 36
8.5 VESSEL SPEED ............................................................................................................... 36
8.6 ANCHORED VESSELS ....................................................................................................... 37
8.7 RECREATIONAL VESSEL ACTIVITY ........................................................................................ 38
8.8 FISHING VESSEL ACTIVITY ................................................................................................. 42
9.0 MARINE TRAFFIC SURVEY ............................................................................................. 48
9.1 INTRODUCTION ............................................................................................................. 48
9.2 MARINE TRAFFIC ........................................................................................................... 48
9.3 VESSEL LENGTH ............................................................................................................. 55
9.4 VESSEL DRAUGHT .......................................................................................................... 57
9.5 VESSEL COURSE ............................................................................................................. 58
9.6 VESSEL SPEED ............................................................................................................... 58
9.7 ANCHORED VESSELS ....................................................................................................... 59
9.8 RECREATIONAL VESSEL ACTIVITY ........................................................................................ 60
9.9 FISHING VESSEL ACTIVITY ................................................................................................. 61
9.10 VESSELS TRANSITING THE PROJECT AREA ............................................................................ 62
10.0 HAZARD WORKSHOP .................................................................................................... 64
10.1 INTRODUCTION ............................................................................................................. 64
10.2 ATTENDANCE ................................................................................................................ 64
10.3 HAZARD WORKSHOP PROCESS .......................................................................................... 65
11.0 CONSULTATION ............................................................................................................ 67
11.1 INTRODUCTION ............................................................................................................. 67
11.2 KEY POINTS/OBSERVATIONS ............................................................................................. 67
11.3 COMMENTS .................................................................................................................. 71
12.0 FORMAL SAFETY ASSESSMENT ..................................................................................... 73
12.2 SIGNIFICANCE CRITERIA ................................................................................................... 73
12.3 CONSTRUCTION IMPACTS ................................................................................................ 76
12.4 OPERATIONAL IMPACTS .................................................................................................. 80
13.0 CUMULATIVE IMPACTS ................................................................................................ 90
14.0 REVIEW OF MITIGATION MEASURES ........................................................................... 91
14.1 INTRODUCTION ............................................................................................................. 91
15.0 RESIDUAL IMPACTS ...................................................................................................... 93
16.0 SUMMARY .................................................................................................................... 96
17.0 REFERENCES ................................................................................................................. 97
Tidal Lagoon Swansea Bay plc

Figure 1- 1 General chart overview ............................................................................................ 1
Figure 1- 2 Detailed chart overview of the Project area ........................................................... 2
Figure 1- 3 Navigational features in close proximity to the Project .......................................... 9
Figure 1- 4 Anchorage areas relative to Project area .............................................................. 11
Figure 1- 5 Aids to Navigation within 5nm of the Project ........................................................ 12
Figure 1- 6 Sailing directions (UKHO, 2011) ............................................................................. 13
Figure 1- 7 Dredging sites in relation to the Project ................................................................ 14
Figure 1- 8 Renewable energy developments.......................................................................... 15
Figure 1- 9 Charted wrecks within 5nm to the Project ............................................................ 16
Figure 1- 10 Tidal Diamonds A and C on Admiralty Chart 1161-0 ........................................... 18
Figure 1- 11 Sea King HAR3A Helicopter .................................................................................. 20
Figure 1- 12 SAR helicopter base relative to the Project ......................................................... 21
Figure 1- 13 RNLI stations in proximity to the Project ............................................................. 22
Figure 1- 14 MAIB incident locations by type within 5nm of the Project Jan 2002 - Dec 2011
.................................................................................................................................................. 24
Figure 1- 15 RNLI incident locations by type within 5nm of the Project 2001 - 2010 ............. 25
Figure 1- 16 Incidents by RNLI station attending 2001 - 2010 ................................................. 26
Figure 1- 17 AIS data within 5nm buffer (28 days July 2012) .................................................. 27
Figure 1- 18 AIS data within 5nm buffer (28 days October 2012) ........................................... 28
Figure 1- 19 Daily number of unique vessels (28 days July 2012) ........................................... 28
Figure 1- 20 Daily number of unique vessels (28 days October 2012) .................................... 29
Figure 1- 21AIS vessel tracks Busiest day (3 July 2012) ........................................................... 30
Figure 1- 22 Vessel types identified within 5nm buffer (28 days July 2012) ........................... 30
Figure 1- 23 Vessel types identified within 5nm buffer (28 days October 2012) .................... 31
Figure 1- 24 AIS Cargo tracks (28 Days July 2012).................................................................... 31
Figure 1- 25 AIS Tug tracks (28 Days July 2012) ....................................................................... 32
Figure 1- 26 Vessel AIS tracks Other ships (28 Days July 2012) ............................................... 32
Figure 1- 27 AIS Cargo vessel tracks (28 Days October 2012) .................................................. 33
Figure 1- 28 AIS Tug tracks (28 Days October 2012) ................................................................ 33
Figure 1- 29 AIS Other ships tracks (28 Days October 2012) ................................................... 34
Figure 1- 30 Vessel length distribution (56 days over July and October 2012) ....................... 34
Figure 1- 31 AIS Tracks for vessels with the greatest lengths .................................................. 35
Figure 1- 32 Vessel draught distribution (56 Days over July and October 2012) .................... 35
Figure 1- 33 AIS Tracks for vessels with the deepest draughts ................................................ 36
Figure 1- 34 Average speed (56 Days over July and October 2012) ........................................ 37
Figure 1- 35 Plots of Anchored vessels (56 days over July and October 2012) ....................... 38
Figure 1- 36 Tracks for recreational vessels (28 Days July 2012) ............................................ 39
Figure 1- 37 AIS Vessel tracks for recreational vessels (28 Days October 2012) ..................... 39
Figure 1- 38 Recreational vessel Scorpio .................................................................................. 40
Figure 1- 39 Recreational vessel Riverdance ............................................................................ 40
Figure 1- 40 RYA recreational routes overview ....................................................................... 42
Figure 1- 41 AIS Tracks Fishing vessels (28 Days July 2012) ..................................................... 43
Figure 1- 42 AIS Tracks Fishing vessels (28 Days October 2012) .............................................. 43
Figure 1- 43 Fishing Vessel MFV Z39 Zuiderzee ....................................................................... 44
Figure 1- 44 Fishing Vessel Z.19 ............................................................................................... 44
Figure 1- 45 Fishing vessel sightings data (2005-2009) ........................................................... 45
Figure 1- 46 Gear type from sightings fishing data (2005-2009) ............................................. 46
Tidal Lagoon Swansea Bay plc

Figure 1- 47 Activity from sightings fishing data (2005-2009) ................................................. 46
Figure 1- 48 Fishing vessel satellite data (2009) ...................................................................... 47
Figure 1- 49 Overview of tracks within 5nm of the Project ..................................................... 49
Figure 1- 50 Detailed overview of tracks within the Project area ........................................... 49
Figure 1- 51 Vessel type distribution identified during August 2013 ...................................... 50
Figure 1- 52 Unique vessels per day within 5nm and crossing the Project area ..................... 51
Figure 1- 53 Busiest day within 5nm buffer (25 August 2013) ................................................ 52
Figure 1- 54 Busiest day within the Project area (26 August 2013) ......................................... 52
Figure 1- 55 Quietest day (15 August 2013) ............................................................................ 53
Figure 1- 56 Tugs (14 Days August 2013) ................................................................................. 53
Figure 1- 57 Cargo vessels (14 Days August 2013) ................................................................... 54
Figure 1- 58 Other vessels (14 Days August 2013) ................................................................... 54
Figure 1- 59 Vessel length distribution (14 Days August 2013) ............................................... 55
Figure 1- 60 Vessel length thematic map (14 Days August 2013) ........................................... 55
Figure 1- 61 Vessel length thematic map detailed view (14 Days August 2013) ..................... 56
Figure 1- 62 Vessels with the greatest length .......................................................................... 56
Figure 1- 63 Photo of the bulk carrier Tenshu Maru taken on 20 August 2013 ...................... 57
Figure 1- 64 Vessel draught distribution (14 Days August 2013) ............................................. 57
Figure 1- 65 Photo of the bulk carrier CIS Captain Veniamis taken on 21 August 2013.......... 58
Figure 1- 66 Deepest vessel draught track ............................................................................... 58
Figure 1- 67 Average speed (14 Days August 2013) ................................................................ 59
Figure 1- 68 Library Photograph of the RNLI Lifeboat D-725 (© RNLI) .................................... 59
Figure 1- 69 Anchored vessels (14 Days August 2013) ............................................................ 60
Figure 1- 70 Recreational vessels (14 Days August 2013) ........................................................ 61
Figure 1- 71 Fishing vessels (14 Days August 2013) ................................................................. 62
Figure 1- 72 Indicative layout of dolphin piles ......................................................................... 78
Figure 1- 73 Indicative layout of dolphin piles ......................................................................... 78
Tidal Lagoon Swansea Bay plc

Abbreviations
AIS - Automatic Identification System
ALB - All-Weather Lifeboat
AtoN - Aid to Navigation
BMAPA - British Marine Aggregate Producers Association
BTA - British Tugowners Association
CA - Cruising Association
CAST - Coastguard Agreement on Salvage and Towage
CNIS - Channel Navigation Information Service
DECC - Department for Energy and Climate Change
ERCoP - Emergency Response Cooperation Plan
GIS - Geographical Information System
GLA - General Lighthouse Authority
GRT - Gross Registered Tonnes
GT - Gross Tonnage
HMCG - HM Coastguard
ILB - Inshore Lifeboat
LLA - Local Lighthouse Authority
MAIB - Marine Accident Investigation Branch
MCA - Maritime and Coastguard Agency
MEHRA - Marine Environmental High Risk Area
MGN - Marine Guidance Note
MHWN - Mean High Water Neaps
MHWS - Mean High Water Springs
MLWN - Mean Low Water Neaps
MLWS - Mean Low Water Springs
MMO - Marine Management Organisation
MOC - Maritime Operations Centre
MOD - Ministry of Defence
MRCC - Maritime Rescue Co-ordination Centre
MRSC - Maritime Rescue Sub-Centre
nm - Nautical Miles
OREI - Offshore Renewable Energy Installations
PEXA - Practice and Exercise Area
PLN - Port Letter and Number
REZ - Renewable Energy Zones
RNLI - Royal National Lifeboat Institution
RYA - Royal Yachting Association
SAR - Search and Rescue
SOSREP - Secretary of State's Representative for Salvage and Intervention
THLS - Trinity House Lighthouse Service
UCG - Underground Coal Gasification
UK - United Kingdom
UKHO - United Kingdom Hydrographic Office
VTS - Vessel Traffic Services
Tidal Lagoon Swansea Bay plc

1.0 Introduction
1.1 Background
1.1.0.1 Anatec has been commissioned by Tidal Lagoon Swansea Bay plc (TLSB) to undertake a
Navigation Risk Assessment (NRA) to support the application for development consent
for the proposed tidal lagoon generating station (the "Project") to be situated in
Swansea Bay, Wales.
1.2 Site overview and the Project
1.2.0.1 The Project is located within Swansea Bay, on the south coast of Wales. A major
element of the Project (referred to as “Project area” in the figures contained within this
report) is the construction of the Lagoon, which encloses an area of sea totalling
approximately 3.4nm2 (11.5 km2). The Lagoon will be created by a seawall built from
sediment, rock armour and potentially, Geotubes® as outlined in Chapter 4: Project
Description. A turbine/sluice gate housing will contain a maximum of 16 turbines and 10
sluice gates, and will be located at the south western edge of the Lagoon.
1.2.0.2 A general chart overview of the Project area in the context of the Bristol Channel is
presented in Figure 1-1.

Figure 1- 1 General chart overview
1.2.0.3 A more detailed chart overview of the Project area is presented in Figure 1-2.

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Tidal Lagoon Swansea Bay plc

Figure 1- 2 Detailed chart overview of the Project area
1.3 Construction works and marine traffic
1.3.0.1 A description of the Project and its offshore structures is provided in Chapter 4: Project
Description. The offshore works are briefly outlined below.
1.3.0.2 Offshore works: The offshore works during the construction and operation phases
comprise the following (and their construction): turbines and sluice gates, their housing
structure, gantry cranes and other facilities, such as generators and switchgear;
temporary cofferdam to facilitate the construction of the turbine and sluice gate
housing structure; temporary rock storage areas; seawalls and associated dredging
works; dredging to create boating area; access road on the seawalls including public
realm works, lighting structures and shelters; Offshore Building incorporating operation
and maintenance (O&M) facilities, with integral visitor centre, leisure facilities and
public realm; emergency facilities; works to Swansea Port Channel; demolition of
existing eastern breakwater wall at the entrance to the Port of Swansea; works to Neath
Harbour Channel including the widening of the entrance to the channel and
replacement of its training wall; water quality enhancement works (if required or
implemented); navigation facilities including lighting; reef habitat creation works,
provision of oyster spatting ponds, herring mitigation, potential bird island/raft and
Sabellaria habitat works; and necessary services.
1.3.0.3 It is anticipated that dolphin piles will be used to protect the turbine housing during
operation and to mitigate the risk to vessels of an allision. If these are utilised, then
they will be installed early in the construction phase when the temporary cofferdam is
being constructed and thus provide protection throughout the various phases of the
Project.
1.3.0.4 It is anticipated that construction will start in 2015 and with the main construction
lasting for about three years. Further details of the construction programme are
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